The present invention is related to a light meter for detecting light intensity, particularly a telescopic, waterproof light meter adapted to be used in an aquarium. The aquarium light meter in accordance with the present invention may be used at various depth to precisely detect the intensity of a light source which penetrates through the water.
Conventional light meters must be placed in a location where they are directly exposed to the light. However, in some applications, it is rather difficult to use the conventional light meters to determine whether the light intensity of a specific environment is appropriate. For example, an aquiculturist has to make sure that the light intensity for the aquatic plants, such as water plants or seaweed, is sufficient for their growth. For water plants, the light intensity should be about 80-200 F.C. (Foot Candles, for seaweed about 1,000-2,000 F.C., and for coral 1,500-2,000 F.C.
To date, no light meter can be placed in the water, or placed at various locations and depths of an aquarium to detect the light intensity exposed on the aquatic plants. Therefore, the aquiculturist has to adjust the light intensity based on visual judgment and personal working experience. Nevertheless, such judgment is unreliable. If the light intensity is too high, harm may be done to the fish. If the light intensity is too low, the photosynthesis of the aquatic plants will be adversely affected, thereby jeopardizing the growth of the plants.